Emit a PrepareScanEvent
This MR is related to #2705 (closed) and related to scan data publishing inside Redis.
This introduce a PrepareScanEvent
- It is emitted just after the whole devices was prepared, and just before any data was emitted
- This is exposed in client side as
on_scan_started
- The previously called
on_scan_started
was renamedon_scan_created
Client side code can monitor the scans the following way:
on_scan_created
- prepare the devices
on_scan_started
- the bunch of data
on_scan_finished
This will allow to update the scan_info
with updated metadata from prepared devices.